The diagnosis of pathological states or other conditions in human beings as well as animals is more and more accomplished by the application of immunological principles, utilized to determine the presence of antibodies or antigens in a body fluid of the subject.
Within the various known testing procedures like the agglutinationtest, the radioimmunoassay, the enzymeimmunoassay, the immunofluorescence or the immunodiffusion, the agglutinationtest is considered as being cheapest, most simple and quick.
In an agglutinationtest, carriers are utilized in order to make it possible to visually or photometrically discern the formed antigen-antibody complexes which have very small sizes. Among the carriers which have been employed are sheep and human erythrocytes, bacterial cells, bentonite, latex particles, e.g., polystyrene, or carboxylated copolymers of styrene and butadiene, anionic phenolic resins and finely divided diazotized amino cellulose.
The known carriers are however limited in their applicability and usefulness in immunological diagnostic procedures since the corresponding immunological reagents show in many instances a lack of sensitivity and/or a poor stability.
In particular, it has not been possible to develop an agglutinationtest for the determination of myoglobin in the urine of patients with suspected myocardial infarction, because the known immunological carriers are not satisfying for attaching myoglobin under retention of its immunological properties or do not show a sufficient stability. The known methods for determining myoglobin in urine like the radial immunodiffusion are expensive and cumbersome. In particular, they do not allow a quick estimation of myoglobin in urine, which the physician could carry out at the bedside of the patient with suspected myocardial infaction.
There is thus a need for a carrier which will form, with a wide spectrum of immunologically active materials, in particular with myoglobin, a diagnostically useful reagent which is stable, specific, sensitive and provides an easily ascertainable visual or photometric evaluation in the minimum of time.